Varnishing preparation



' No Drawing.

Patented Feb. 10, 1931 "UNITED STATES PATENT OFFICE K AZUO TAKETMURA, OFMINAMI-KU OSAKA, J'AIAN, ASSIGNOR OF FIITY PER CENT TO KAZUE OIWA, OFKAWABEGUN HYOGO-KEN, JAPAN VARNISHING PREPARATION This invention hasreference to varnishes and has for its object the provision of a noveltype of varnish the composition of which consists of certain amounts ofsubstances such as nitro-cellulose, amyl-acetate, ether, acotone,alcohol, yellow prussiate of potash, (libutyl ester and pulverizedbamboo. The formula for dibutyl ester (or butanol tartrate or dibutyltartrate, as it is sometimes called) is (0 11 2G H O acid.

In the process to manufacture the varnish according to the invention,itis necessary to first dissolve nitro-cellulose in solvents such asamyl-acetate, ether and acetone. The solution which has then beendiluted with alcohol or benzol, is mixed with dibutyl ester and properlyagitated. To the liquid are further added the required amounts of yellowproduct obtained by this treatment bears by itself a shade somewhatyellowish, however if it is mixed with one or more suitable pigments itcan appear in any desired colour.

In the above process, it is apparent that nitro-cellulose is thoroughlydissolved in amyl-acetate, ether and acetone, while the solution soobtained is also capable of being well thinned down with a mixture ofalcohol or benzol. On account of these pro erties of the substancesemployed, it is wit ease to give the fluid such a viscosity as may fitfor its application by brushing or spraying. As the result of theaddition of dibutyl ester to the solution, the fluid acquires a' desiredelasticity of the resulting film when it is aplied as a coating. Inexperiment, it has been proved that a metal plate or wirecoated with thevarnish according to the invention could be bent or wound up as much asdesired without causing any cracking or flaking on the film of thecoating. Further advantage has been tested in drilling a metal work whenI witnessed that the film of the varnish coated thereon was peeled outentirely in one piece with the flakes of the metal cut ofi, therebyimparting no harm to the surrounding portions.

To make the elasticity and viscosity of the product greater, I have usedpulverized bam- -It is an ester of tartaric Application filed'August 3,1926. Serial No. 126,931.

boo, which, when mixed with the fluid, in creases "the durability andresisting power of the varnish. In this respect, I have found pulverizedbamboo to be a very useful ibody.

In the actual process for the manufacture, the following composition maybe one which is appropriate Grams Nitro-cellulose 15 Amyl-acetate 35Ether 1O Acetone 10 Alcohol 20 Dibutyl ester 5' Yellow prussiate ofpotash 3 Pulverized bamboo 5 The given amounts of the substances shouldbe treated as described above.

In use, if the varnish is applied to ironprussiate of potashandbamboopowder. The "Work, yellow potassium.prussiate is bined withiron, forming iron cyanide which deposits by itself on the surfaceof'the work in the form of film, serving as the coating foranti-corrosion. This makes the substance especially suitable for use inconnection with ironwork. In the case where the varnish is applied tothe bottom of a boat, the presence of cyanic acid in the fluid preventsshells from attaching to the surface, and moreover the smooth evencoating diminishes the water-resisting power of the boat to a greatextent.

By reason of the-highly insulating properties, the varnish according tothe invention is capable of being used as coating for electric wires andwindings, in place of silk, gum and other known substances. Theadvantage of the present manufacture over these known substancesconsists not only in the diminutionof the space it occupies, but in thecheapness of cost.

Further advantage may be pointed out in fact that the varnishmanufactured as above described, leaves, when applied to woodwork, nobrush-marks, imparting an evenly coated glossy finish on the surface ofthe work. This can hardly be expected of the known paints or varnishes.A

' Having now particularly described and ascertained the nature of mysaid invention and in what manner the same is to be performed, I declarethat what I claim is A varnish comprising nitro-cellulose, yellowprussiate of potash and pulvenzed bamboo.

Intestimony whereof I hereunto aflix my KAZUO 'TAKEMURA.

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